ABSTRACT
This chapter describes implementation details of a Graphics processing unit (GPU)-assisted material aging simulation, which is based on customizable aging rules and material transport through particles. The simulation machinery is partly CUDA-based and partly rasterization-based to exploit the advantages of both sides. In fact, it is driven by interplay of a number of modern GPU features, including GPU ray tracing, dynamic shader linkage, tessellation, geometry shaders, rasterization-based splatting and transform feedback. The amount of material carried by gammatons or resting on a surface— the latter is stored in texels of the atlas—is assignable to eight available slots. The gammaton material is updated afterwards in a separate transform feedback pass by feeding the gammatons into the rendering pipeline as point list. The chapter utilizes a simple powerful set of rules to obtain the most common aging effects, including dirt, rust, organic, and water precipitate, and displayed those in a few seconds in which the scene progressively and visibly ages.
